Draft yoke



Oct. 31, 1933.

H. H. WOLFE 1,933,200

DRAFT YOKE Filed Aug. 27, 1930 '2 Sheets-Sheet l Oct. 31, 1933.

H. H. WOLFE" DRAFT YOKE Filed Aug. 27, 1930 2 Sheets-Sheet 2 Patented Oct. 31 1933 DRAFT YOKE I-Iarry H. Wolfe, Columbus, Ohio, assignor toThe Buckeye Steel Castin Ohio gs Company, Columbus,

Application August 27, 1930. Serial No. 478 ,217

1 Claim.

This invention relates to improvements in draft yokes for use with double acting draft gears.

The selective travel or double acting gear is .3 a type of draft that has recently come on the market, and as it functions somewhat difierentlg from the ordinary draft gear, I have incorporated certain features in the conventional draft yoke in order to adapt ,it to use with this new type of gear.

In freight car service the greatest force on the couplers is the buffing forces which are due to backing a train into a cut of cars in order to couple that out to the tr in in classifying yards where cars cut loose and are brought to a full stop by the coupler on the moving car striking the coupler on other cars on the classifying tracks.

The pulling forces are, of course, due to starting a train in forward motion and pulling the train along the track, and as mentioned before, are not as great as the impact or buffing forces of a loaded car.

The double acting draft gear has practically twice the capa ity in buff as it has in pull, but requires modification in the yoke.

The primary purpose of the present invention is to specially construct the conventional type of yoke to accommodate the double acting draft gear.

With the foregoing object outlined and with other objects in View which will appear as the description proceeds, the invention consists in the novel features hereinafter described in detail, illustrated in the accompanying drawings, and more particularly pointed out in the appended claim.

In the drawings,

Figure l is a horizontal longitudinal sectional view of a coupler mechanism equipped with. my

improvements.

Figure 2 is a vertical sectional View of the same partially in side elevation.

Referring to the drawings, 1 designates the modiiied yoke, 2 the new type double acting draft which can be compressed at both ends ins cad of at one end, as is usual withthe conventional gearwith compressive travel at one end only. A vertical key passes through the 59 draft and through both straps of the yoke and rests on a transverse support 3a which is secured to the center sills 32;. A horizontal key a connects the yoke and coupler shank in the usual manner.

' The draft gear includes a front follower plate 5 and a rear follower plate 6 which transmit the-pulling and buffing forces respectively to the front draft lugs '7 and the rear draft lugs 8, as the draft gear yields, due to. these forces.

9 is the usual combined center brace and rear draft lugs, and 10 is the conventional combined striking casting and front draft lugs. The ordinary coupler shank is shown at 11.

The coupler shank has a key slot 12 which is only slightly larger than the key 4, while the key slot 13 in the yoke accommodates the key 4 w iich beers only at the front end of this slot, and the opening 14 at each side of the striking casting 10, permits travel of the key 4 which does not bear at either end of the opening 14. It will thus be understood that the key 4 has very little movement in the coupler shank, greater movement in the yoke and still greater movement in the slots 14.

The yoke has a key slot 15 in its straps and the key bears only at the rear end of this slot, while the key slot 16 in the draft gear is just large enough toperinit the insertion of the key 3, this key bearing at the front end of the slot in the draft gear, whether the force is pull or buff.

These parts function as follows: When a pulling force is applied to the coupler shank 11, it is trans itted immediately to the yoke 1, by means of the key 4, and the yoke then transfers this force through the key 3 to the draft gear 2, which compresses against the front follower 5 by reducing the distance A; the compression absorbing a large portion of the shock. As the follower 5 bears against the lugs '7, which are riveted to the center sills, the pulling force is transmitted to the car body. It will be understood from the above that only the front end the draft gear comes into action during pull.

When a buffing force is applied tothe coupler shank, this force is transmitted by the butt end of the shank 17 to the plate 5, which in turn compresses the draft gear against the rear follower 6, and as this follower bears against the rear draft lugs 8, which are riveted to the center sills of the car, the buffing force after being partially absorbed by the gear, is transmitted to the car body.

It is obvious that in buff, the draft gear is compressed by reducing the distance both at A and B. Also the yoke is slid back by the key 3, a distance equal to one half the total gear compression. The construction line C indicates the extreme buffing position of the yoke under full draft gear compression.

In accordance with my invention, the yoke is modified to accommodate this new type of draft gear; the modification consisting principally of the key slot 15 and the reinforcements 18, the

former normally providing a clearance between the front ends of the slots and the front edge of the key 3, and the latter strengthening the yoke where the key bears against the same. In this connection it will be noted that the key 3 only bears at the rear end of the key slot 15 under load, there being sufficient clearance at the front end of the slot 15 and the rear end of the slot 13 in the nose of the yoke, to prevent load bearing contact. Although it is only necessary to have the slot 15. slightly longer than the width of the key 3, for the proper functioning of the assembled parts, I have shown some additional clearance at the front end of this slot to provide ease of assembling.

It will also be seen that the straps 20 do not ordinarily carry any stress due to pull or buff, and the butt end 19 of the yoke acts mainly as a tie, whereas, in the usual yoke full pulling forces are carried to the butt end of the yoke through the full length of the straps. However, if the key 3 or the key slot 16 in the draft gear becomes badly worn, some of the pulling force will be taken on the butt end of the yoke, that is, until the compression of the gear is sufficient to make contact between the key, the yoke and the draft gear.

At this point it will be noted that each reinforcement 18 is of its greatest thickness adjae cent the portion'of the strap 20 through which the slot 15 extends, and from this point, the outer surface of the strap gradually inclines away from the slot.

By the term double-acting draft gear used in the appended claim, I do not refer to the conventional draft gearv which acts both in draft and buff, but to a draft gear of the type that has approximately twice the capacity in buff as in pull.

From the foregoing it is believed that the construction, operation and advantages of the invention may be readily understood by those skilled in the art and I am aware that changes may be made in the details disclosed without departing from the spirit of the invention as expressed in the claim.

What I claim and desire to secure by Letters- Patent is:-

A draft mechanism comprising center sills, front and rear draft lugs arranged between the sills, a one-piece vertical hooded yoke positioned between said sills and consisting of top and bottom straps, a front hood and a rear butt, said hooded end of the yoke having horizontal key slots, a double acting draft gear positioned Within the yoke and provided with a vertical slot in its medial portion, said yoke straps also having vertical slots in their medial portions, a key extending through said vertical slots for keying the yoke to the draft gear and causing the entire medial portion of the draft gear to move with the yoke during buff and draft, said gear including front and rear followers normally engaging respectively with the front and rear draft lugs, said butt limiting the rearward movement of the rear follower when the latter is positioned forwardly of the rear draft lugs, said yoke cooperating with the followers to maintain thezn in vertical positions, a coupler shank extending into the hood of the yoke and normally engaging the front follower, for moving the latter independently of the yoke during buff, and a horizontal key of less width than the length of said horizontal slots extending through said shank and the horizontal slots for causing the yoke to move forwardly with said shank.

HARRY H. WOLFE. 

